1. Field of the Invention
The present invention relates to a powder conveyance device, and more particularly to a toner conveyance device that conveys waste toner discharged from an image creating mechanism of an image forming apparatus to a collection unit. The present invention also relates to a process cartridge and the image forming apparatus that comprise the toner conveyance device.
2. Description of the Related Art
In a known image forming apparatus such as a copier, a printer, a facsimile device or a compound device thereof, waste toner removed from the surface of an image carrier is conveyed to a collection unit by conveying means. The conveying means may be formed by having a conveyor belt provided with a plurality of concavo-convex portions on the conveyance surface thereof travel around a loop-shaped groove, for example (see Japanese Unexamined Patent Application Publication H11-73078). The toner is accommodated in the concave portions of the conveyor belt, conveyed to the collection unit, dropped into the collection unit, and thereby collected.
However, with conveying means employing a conveyor belt such as that disclosed in this publication, it is impossible to drop all of the conveyed toner into the collection unit, and a small amount of toner remains on the concavo-convex portions of the conveyor belt. As the residual toner deteriorates, it sticks to the conveyor belt, leading to a reduction in the volume of the recess portions and a corresponding reduction in conveyance ability.